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					What sells usability?




       Nigel Bevan

   nigel.bevan@serco.com
  Serco Usability Services
   and University of York
           UK



                             1
Why is usability important?


 The individual components of usability make business sense:

   – Effective: success in achieving goals

   – Efficient: productivity, staffing, waiting time in line

   – Satisfied: willingness to use the system

   – Risk: reduced business risk




                                                                2
    Potential cost benefits                                          Product sales can be increased as a result of
                                                                       the usability of the product:
                                                                        – Improving the competitive edge by marketing the
 Development costs can be reduced by:                                      product or service as easy to use
    – Producing a product that has only relevant functionality          –   Increasing the number of customers satisfied with the
    – Detecting and fixing usability problems early in the                  product who will make repeat purchases and
        development process                                                 recommend the product to others
    –   Reducing the cost of future redesign or radical change of       –   Obtaining higher ratings for usability in product
        the architecture to make future versions of the product             reviews

    –
        more usable
        Minimizing or eliminating the need for documentation
                                                                     Employers can benefit from easier to use
    –   Redesigning web sites to increase revenue, not just to
                                                                       systems in the following ways:
        change the image                                                – Faster learning and better retention of information
    –   Reducing the risk of product failure                            – Reducing task time and increased productivity
                                                                        – Reducing employee errors that have to be corrected
 E-commerce sales can be improved by increasing                            later
   the number of web site customers who will:                           –   Reducing employee errors that impact on the quality
    – Be able to find products that they want                               of service
    – Find supplementary information easily (e.g. delivery,             –   Reducing staff turnover as a result of higher
        return and warranty information)                                    satisfaction and motivation
    –   Be satisfied with the web site and make repeat purchases        –   Reducing time spent by other staff providing
    –   Trust the web site (with personal information and to                assistance when users encounter difficulties
        operate correctly)                                           E. Suppliers and/or employers can benefit
    –   Not require any support, or use the web site for support       from reduced support and maintenance costs
        rather than calling the support center
    –   Recommend the site to others
                                                                       in the following ways:
    –   Support and increase sales by other channels                    – Reducing support and help line costs
                                                                        – Reducing costs of training
                                                                        – Reducing maintenance costs                      3
So why is usability often ignored?


 Believed to add to project risk
   – Additional time and cost
   – Outside area of experience
   – No established process for usability

 Not specified in requirements
   – Not my responsibility
   – Customers don’t ask for it

 Intangible
   – Every user wants something different




                                            4
Barriers to uptake


 What motivates an organisation (or project) to invest in usability?

 The barriers, perceived:
   – Increased cost
   – Increased development time
   – Therefore increased risk?




                                                                        5
Main motivator for investing in usability


 The requirements/RFP mentions ease of use
   – What is the least we can do to address this?


 This project has a problem with usability
   – Usability can help solve it: ie risk reduction

 Senior usability convert
   – Usability is important to our business success

 We realise that usability is important for success
   – Usually for consumer products and web sites




                                                       6
Selling the concept?


 Usability can
   –   improve your productivity
   –   Improve your sales
   –   Improve the quality of your product
   –   Reduce the risk of product failure
   –   Improve your process
   –   Drive innovation (IBM)
   –   Improve affecive/emotional design (Arnie)


 Usability helps design products to match user needs (Arnie)

 Usability is acknowledged good practice


                                                                7
The importance of user requirements

 Standish Group found that
     15%     of projects failed
     51%     were partially successful

 Main causes were poor user requirements:
     13.1%   Incomplete requirements
     12.4%   Lack of user involvement
     10.6%   Inadequate resources
     9.9%    Unrealistic user expectations
     9.3%    Lack of management support
     8.7%    Requirements keep changing
     8.1%    Inadequate planning
     7.5%    System no longer needed




                                             8
One number for usability


 Jeff Sauro has shown that it can be done
   – Sauro and Kindlund, UPA 2005
     Making Sense of Usability Metrics: Usability and Six Sigma


 Satisfaction questionnaire can provide a single number

 But the weighting is context-dependent?
   – The individual components of usability make business sense:
          Effective: success in achieving goals
          Efficient: productivity, staffing, waiting time in line
          Satisfied: willingness to use the system
          Risk: reduced business risk




                                                                     9
But, to quote Allen Cooper


 If you were a plastic surgeon, would you go down the road knocking
  on doors, and telling the person who comes to the door:

   – “I can see you are ugly: but I am a plastic surgeon and I can help you!”




                                                                                10
Tailor the message for the audience

 No one size fits all?
   – Adapt the message to the audience?
   – But how do you know what the audience wants to hear?

 Need to analyse the business environment and the motivators and
  constraints for the gatekeeper

 Tailor the message to the context of use. What matters to the gate
  keeper?
   –   Increased revenue?
   –   Decreased costs?
   –   Reduced risk of failure of the product?
   –   None of these: no sell!



                                                                       11
12
Essential prerequisites for usability




                                        13
 Human centred design process for interactive systems:
 ISO 13407 (1999)

                       1. Plan the human
                        centred process

Meets requirements

                        2. Specify the
                        context of use
 5. Evaluate designs                       3. Specify user and
     against user                             organisational
    requirements                              requirements
                       4. Produce design
                            solutions
                                                             14
Essential activities to achieve usability


  Plan          Specify              Specify            Design         Evaluate against
Process      Context of Use        Requirements        Solutions        Requirements


                                         System lifecycle


      feasibility                  requirements         design      implement       release

 1.Stake-      2. Context of    4. Usability       6. Prototyping   8.Evaluation    10. Collect
 holder        use              requirements                                        feedback
 meeting                                           7. Style guide   9. Usability
               3.Scenarios      5. Evaluate                         testing
                                existing system




                           www.usabilitynet.org/trump/ucdmethods


                                                                                                  15
ISO TR 18529
Human-centred lifecycle processes descriptions

HCD.1 Ensure HCD content in system strategy
HCD.2 Plan and manage the HCD process
HCD.3 Specify the user and organisational requirements
HCD.4 Understand and specify the context of use
HCD.5 Produce design solutions
HCD.6 Evaluate designs against requirements
HCD.7 Introduce and operate the system

Can be used to assess organisational capability and identify needs
  for process improvement



                                                                     16
ISO TR: 18529
Human-centred lifecycle processes descriptions


Understand and Specify User and Organizational
  Requirement and Context of Use

2.1 - Clarify and document system goals
2.2 - Analyze stakeholders
2.3 - Assess risk to stakeholders
2.4 - Identify, document and analyze the context of use
2.5 - Define the use of the system
2.6 - Generate the stakeholder, user and organizational requirements
2.7 - Set usability objectives



                                                                  17
What is usability?




                     18
ISO/IEC 9126
Software quality characteristics

1991

   Functionality
   Efficiency
   Reliability
   Usability
   Maintainability
   Portability




                                   19
ISO/IEC 9126-1 Software Product Quality Model (1991)

              functionality       reliability

                 accuracy             maturity
                 suitability      fault tolerance
              interoperability     recoverability
                  security           availability


                usability         efficiency

              understandability
                learnability      time behaviour
                 operability         resource
               attractiveness        utilisation



             maintainability      portability
               analysability       adaptability
               changeability       installability
                  stability       co-existence
                 testability      replaceability



                                                       20
ISO 9241-11 Guidance on Usability (1998)


 Usability The extent to which a product can be used by specified
 users to achieve specified goals with effectiveness, efficiency and
 satisfaction in a specified context of use

 Effectiveness : The accuracy and completeness with which users
 achieve specified goals.

 Efficiency : The resources expended in relation to the accuracy and
 completeness with which users achieve goals.

 Satisfaction : The comfort and acceptability of use




                                                                       21
Usability model



                                  personal
                                environment

 goals
                                   user

                                                        user
                                                    satisfaction
                                      interaction
                   physical           tasks            output:
                  environment
                                                    effectiveness
   social and
                                                      efficiency
 organisational
  environment                    product

                                 technical
                                environment




                                                                    22
ISO/IEC 9126-1 Software Product Quality Model

                             q u a l it y i n u s e

          functionality                               reliability

             accuracy                                     maturity
             suitability                              fault tolerance
          interoperability                             recoverability
              security                                   availability


           usability                                  efficiency

         understandability
           learnability                               time behaviour
            operability                                  resource
          attractiveness                                 utilisation



         maintainability                              portability
           analysability                                adaptability
           changeability                                installability
              stability                                co-existence
             testability                               replaceability
                                                                         23
Quality in use

 The extent to which a product used by specific users meets their needs to
  achieve specific goals with effectiveness, productivity, safety and
  satisfaction in specific contexts of use

 Effectiveness
   – The extent to which users are able to achieve specified goals with accuracy and
      completeness in a specified context of use
 Productivity
   – The extent to which users are able to expend appropriate amounts of resources in relation
      to the effectiveness achieved in a specified context of use
 Satisfaction
   – The extent to which users are satisfied in a specified context of use
 Safety/Risk
   – The extent to which risk of harm to people, business, software, property or the environment
      is acceptable in a specified context of use




                                                                                             24
How do you know a consumer product is usable?




  Can’t tell from appearance in the shop

  Difficult to tell from a demonstration

  By the time you find out it is too late …

  So no incentive for suppliers




                                                25
Plan for Usability Assurance Statements


1990

 Planned that ISO 9241-11 would provide Usability Assurance
  Statements

 Usability test results giving effectiveness, efficiency and satisfaction
  in a particular context of use




                                                                         26
But not everyone wants their usability assured …




                                                   27
US computer company opposed usability assurance
statements

 The results could be misinterpreted

 They did not wish to be obliged to produce such statements

 US computer company around the world would lobby for vote no
  votes



 So usability assurance statements were dropped




                                                                 28
 Common Industry Format for usability test reports


 NIST initiative in 1998
   – National Institute of Standards and Technology
 Suppliers provide standard test reports to purchasers
 Suppliers included:
   – IBM, Microsoft, HP, Sun, Oracle, Compaq
 Purchasers included:
   – Boeing, Northwest Mutual Life, State Farm Insurance, Fidelity, Kodak
 Reports provided in confidence
 Could permit comparisons




                                                                            29
Common Industry Format usability tests


Objectives

 Raise the profile of usability in procurement
 Encourage suppliers to work more closely with purchasers to
  understand user needs

 A common format for sharing usability data
 Reduce uncontrolled overhead costs of usability problems
 Enable purchasers to compare usability




                                                                30
CIF motivation


 Boeing
     “We traditionally have had little visibility of how usable a product will be or how much
     training and support users will need. This has made it difficult to compare products, to
     plan for support, or estimate total cost of ownership.”
 US WEST
     “US WEST has been actively participating in [the CIF] initiative and will clearly benefit
     from the results of this effort such as a standard testing process for usability, a standard
     specification for reporting usability tests, and other techniques to enable us to partner
     more effectively with our vendors.”
 State Farm Insurance
     “We have found it difficult to identify software products that meet our needs without
     contributing to excessive overhead, increasing support costs, or negatively impacting
     employee productivity or morale. If successful the [CIF] initiative should result in the
     development of better, more usable software for all of industry.”




                                                                                                    31
How it should work

 Purchaser requests supplier to provide a CIF report
   – initially as part of agreed trials

 The supplier may already be planning a usability test
   – may have to adapt the test plan to be suitable for CIF report
   or
 The supplier asks the purchaser to carry out the test
   or
 The supplier asks a third party to carry out the test

 The test results help the purchaser decide
   – whether to purchase
   – whether to request changes




                                                                     32
Report format - technical


 Test objectives
 Participants
   – Total number and user groups
   – Key characteristics and capabilities expected
   – How selected: with the key characteristics and capabilities?
 Context of evaluation
   – Task scenarios and task data used
   – Any performance criteria used
   – Physical and computer environment




                                                                    33
Report format - results

 Design
   –   Independent and control variables
   –   Measures used
   –   Any training and assistance given
   –   Task instructions
 Effectiveness
   – % completely and correctly achieving their goals
   – Separate data where assistance was given
 Efficiency
   – Mean time taken to complete the task
   – Standard deviation (and standard error)
 Satisfaction
   – Optional: own scales and/or standard questionnaire



                                                          34
Common Industry Format Standard


 ANSI/NCITS 354

 ISO 25062




                                  35
Why are so many consumer products difficult to use?




  Difficult to assess usability when purchasing

  Corporate purchasers want usability reported in the Common
   Industry Format

  Consumers need a label or statement




                                                                36
ISO 20282: Ease of operation of everyday products
Part 1: Context of use and user characteristics


 Context of use
   –   Are the main goals identified?
   –   Are actions on other equipment influential?
   –   Are environmental factors relevant?
   –   Is privacy or the social environment relevant?




                                                        37
User characteristics

 Psychological and social characteristics
   –   Do cognitive abilities influence ease of operation?
   –   Do knowledge, experience and habit influence ease of operation?
   –   Do cultural differences influence ease of operation?
   –   Does literacy influence ease of operation?
   –   Does language influence ease of operation?
 Physical and sensory
   –   Are body dimensions relevant for ease of operation?
   –   Are strength and biomechanical abilities relevant?
   –   Are visual abilities relevant for ease of operation?
   –   Are auditory abilities relevant for the ease of operation?
   –   Does handedness influence the ease of operation?
 Categories
   – Does age influence the ease of operation?
   – Does gender influence ease of operation?




                                                                         38
39
ISO CD 20282-2: Test method

 A summative test method for measuring usability based on
   – ISO 9241-11 (Guidance on usability)
   – Common Industry Format for usability test reports

 Identify intended context of use and user groups

 Measures
   – Success rate (ease of operation)
   – Task time (efficiency)
   – Satisfaction scale




                                                             40
ISO TS 20282-2: Test method for usability of everyday
products


 Measures
   – Success rate (effectiveness)
   – Task time (efficiency)
   – Satisfaction scale

 Criteria
   – 80% of the intended users can successfully complete the main tasks without
     assistance




                                                                                  41
A manufacturer can use ISO 20282-2 to provide evidence of the ease of
operation of a product for marketing purposes


A manufacturer wants to demonstrate that a videorecorder is very easy to
  program without instructions.
A stratified sample of 50 people who have purchased a videorecorder with the
   intention of programming it to record programmes are recruited who are
   representative in age, education and ownership of brands of videorecorder
   owners.
Each session is expected to take a total of 5-10 minutes, and 2 videorecorders
  are set up with TVs for programming.
Each person is given asked to program the videorecorder to record a specified
  programme in a TV magazine. It is expected that most people will use the
  Videoplus code, but direct programming on the channel and time is also
  acceptable.
The test result is given as the measured success rate together with a
  confidence interval. To be 95% confident that 80% of the user population
  can program the videorecorder, 45 of the 50 people tested will have to be
  successful.


                                                                              42
Not everyone wants their usability assured
               (again) …




                                             43
German computer company opposes the standard


 “The results could be misinterpreted”

 “We do not wish to be obliged to carry out such tests”

 “Remove all reference to consumer products”

 Lobbied for for industry association to vote no

 Tried to raise procedural obstacles to prevent the standard
  progressing




                                                                44
We nearly forgot about requirements!




                                       45
Common Industry Format


         Supplier                Consumer

                         CIF-R
         Usability                 Usability
       requirements              requirements




        Usability test   CIF      Purchase
           report                 decision



                                                46
CIF Requirements

 Context of use
   – Users
           Key characteristics and capabilities of each user group for which requirements are
            provided
   – Goals
           Main goals for each group with scenarios of use
   – Equipment: technical environment
           Computer hardware and software
   – Physical and social environments
   – Scenarios of use for most important goals
   – Training scenarios

 Usability measures
   –   Effectiveness: unassisted completion rate
   –   Efficiency: mean time to achieve goals
   –   Satisfaction: mean score on a satisfaction scale
   –   Relative user efficiency (optional)
                                                                                                 47
CIF Requirements

 Context of use
   – Users
           Key characteristics and capabilities of each user group for which requirements are
            provided
   – Goals
           Main goals for each group with scenarios of use
   – Equipment: technical environment
           Computer hardware and software
   – Physical and social environments
   – Scenarios of use for most important goals
   – Training scenarios

 Usability measures
   –   Effectiveness: unassisted completion rate
   –   Efficiency: mean time to achieve goals
   –   Satisfaction: mean score on a satisfaction scale
   –   Relative user efficiency (optional)

                                                                                                 48
Example: Usability measures

 Task 1: Download SITE guard software
    – Effectiveness: 90% unassisted task completion rate.
    – Efficiency: 10 minutes of user time.
    – Satisfaction: Total SUMI score of 50.

 Task 2: Burn SITE guard software to DVD and launch installer
    – Effectiveness: 90% unassisted task completion rate.
    – Efficiency: 15 minutes of user time.
    – Satisfaction: Total SUMI score of 50.

 Task 3: Prepare SITE guard software for staged install and launch installer
    – Effectiveness: 70% unassisted task completion rate.
    – Efficiency: 25 minutes of user time.
    – Satisfaction: Total SUS or SUMI score of 50.




                                                                            49
What can YOU do about it?
Usability Professionals Association

 World Usability Day
   – 14 November 2006

 Usability Body of Knowledge




                                      50
World Usability Day




                      51
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